A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.
A glycoprotein that is important in the activation of CLASSICAL COMPLEMENT PATHWAY. C4 is cleaved by the activated COMPLEMENT C1S into COMPLEMENT C4A and COMPLEMENT C4B.
The smaller fragment formed when complement C4 is cleaved by COMPLEMENT C1S. It is an anaphylatoxin that causes symptoms of immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE) but its activity is weaker than that of COMPLEMENT C3A or COMPLEMENT C5A.
The smaller fragment generated from the cleavage of complement C3 by C3 CONVERTASE. C3a, a 77-amino acid peptide, is a mediator of local inflammatory process. It induces smooth MUSCLE CONTRACTION, and HISTAMINE RELEASE from MAST CELLS and LEUKOCYTES. C3a is considered an anaphylatoxin along with COMPLEMENT C4A; COMPLEMENT C5A; and COMPLEMENT C5A, DES-ARGININE.
A subcomponent of complement C1, composed of six copies of three polypeptide chains (A, B, and C), each encoded by a separate gene (C1QA; C1QB; C1QC). This complex is arranged in nine subunits (six disulfide-linked dimers of A and B, and three disulfide-linked homodimers of C). C1q has binding sites for antibodies (the heavy chain of IMMUNOGLOBULIN G or IMMUNOGLOBULIN M). The interaction of C1q and immunoglobulin activates the two proenzymes COMPLEMENT C1R and COMPLEMENT C1S, thus initiating the cascade of COMPLEMENT ACTIVATION via the CLASSICAL COMPLEMENT PATHWAY.
The minor fragment formed when C5 convertase cleaves C5 into C5a and COMPLEMENT C5B. C5a is a 74-amino-acid glycopeptide with a carboxy-terminal ARGININE that is crucial for its spasmogenic activity. Of all the complement-derived anaphylatoxins, C5a is the most potent in mediating immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE), smooth MUSCLE CONTRACTION; HISTAMINE RELEASE; and migration of LEUKOCYTES to site of INFLAMMATION.
The sequential activation of serum COMPLEMENT PROTEINS to create the COMPLEMENT MEMBRANE ATTACK COMPLEX. Factors initiating complement activation include ANTIGEN-ANTIBODY COMPLEXES, microbial ANTIGENS, or cell surface POLYSACCHARIDES.
The large fragment formed when COMPLEMENT C4 is cleaved by COMPLEMENT C1S. The membrane-bound C4b binds COMPLEMENT C2A, a SERINE PROTEASE, to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).
C5 plays a central role in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C5 is cleaved by C5 CONVERTASE into COMPLEMENT C5A and COMPLEMENT C5B. The smaller fragment C5a is an ANAPHYLATOXIN and mediator of inflammatory process. The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the MEMBRANE ATTACK COMPLEX.
The larger fragment generated from the cleavage of COMPLEMENT C3 by C3 CONVERTASE. It is a constituent of the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb), and COMPLEMENT C5 CONVERTASES in both the classical (C4b2a3b) and the alternative (C3bBb3b) pathway. C3b participates in IMMUNE ADHERENCE REACTION and enhances PHAGOCYTOSIS. It can be inactivated (iC3b) or cleaved by various proteases to yield fragments such as COMPLEMENT C3C; COMPLEMENT C3D; C3e; C3f; and C3g.
Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. Included are glycoproteins in the various pathways of complement activation (CLASSICAL COMPLEMENT PATHWAY; ALTERNATIVE COMPLEMENT PATHWAY; and LECTIN COMPLEMENT PATHWAY).
A 105-kDa serum glycoprotein with significant homology to the other late complement components, C7-C9. It is a polypeptide chain cross-linked by 32 disulfide bonds. C6 is the next complement component to bind to the membrane-bound COMPLEMENT C5B in the assembly of MEMBRANE ATTACK COMPLEX. It is encoded by gene C6.
A 206-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c (749-954), and C3dg (955-1303) in the presence COMPLEMENT FACTOR H.
A 302-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c, and C3dg (955-1303) in the presence COMPLEMENT FACTOR H. Serum proteases further degrade C3dg into C3d (1002-1303) and C3g (955-1001).
A component of the CLASSICAL COMPLEMENT PATHWAY. C2 is cleaved by activated COMPLEMENT C1S into COMPLEMENT C2B and COMPLEMENT C2A. C2a, the COOH-terminal fragment containing a SERINE PROTEASE, combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).
A 63-kDa serum glycoprotein encoded by gene C9. Monomeric C9 (mC9) binds the C5b-8 complex to form C5b-9 which catalyzes the polymerization of C9 forming C5b-p9 (MEMBRANE ATTACK COMPLEX) and transmembrane channels leading to lysis of the target cell. Patients with C9 deficiency suffer from recurrent bacterial infections.
Molecules on the surface of some B-lymphocytes and macrophages, that recognize and combine with the C3b, C3d, C1q, and C4b components of complement.
A 77-kDa subcomponent of complement C1, encoded by gene C1S, is a SERINE PROTEASE existing as a proenzyme (homodimer) in the intact complement C1 complex. Upon the binding of COMPLEMENT C1Q to antibodies, the activated COMPLEMENT C1R cleaves C1s into two chains, A (heavy) and B (light, the serine protease), linked by disulfide bonds yielding the active C1s. The activated C1s, in turn, cleaves COMPLEMENT C2 and COMPLEMENT C4 to form C4b2a (CLASSICAL C3 CONVERTASE).
A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.
A 80-kDa subcomponent of complement C1, existing as a SERINE PROTEASE proenzyme in the intact complement C1 complex. When COMPLEMENT C1Q is bound to antibodies, the changed tertiary structure causes autolytic activation of complement C1r which is cleaved into two chains, A (heavy) and B (light, the serine protease), connected by disulfide bonds. The activated C1r serine protease, in turn, activates COMPLEMENT C1S proenzyme by cleaving the Arg426-Ile427 bond. No fragment is released when either C1r or C1s is cleaved.
Serum proteins that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host. The complement system is tightly regulated by inactivators that accelerate the decay of intermediates and certain cell surface receptors.
A 93-kDa serum glycoprotein encoded by C7 gene. It is a polypeptide chain with 28 disulfide bridges. In the formation of MEMBRANE ATTACK COMPLEX; C7 is the next component to bind the C5b-6 complex forming a trimolecular complex C5b-7 which is lipophilic, resembles an integral membrane protein, and serves as an anchor for the late complement components, C8 and C9.
Serine proteases that cleave COMPLEMENT C3 into COMPLEMENT C3A and COMPLEMENT C3B, or cleave COMPLEMENT C5 into COMPLEMENT C5A and COMPLEMENT C5B. These include the different forms of C3/C5 convertases in the classical and the alternative pathways of COMPLEMENT ACTIVATION. Both cleavages take place at the C-terminal of an ARGININE residue.
A glycine-rich, heat-labile serum glycoprotein that contains a component of the C3 CONVERTASE ALTERNATE PATHWAY (C3bBb). Bb, a serine protease, is generated when factor B is cleaved by COMPLEMENT FACTOR D into Ba and Bb.
Complement activation initiated by the interaction of microbial ANTIGENS with COMPLEMENT C3B. When COMPLEMENT FACTOR B binds to the membrane-bound C3b, COMPLEMENT FACTOR D cleaves it to form alternative C3 CONVERTASE (C3BBB) which, stabilized by COMPLEMENT FACTOR P, is able to cleave multiple COMPLEMENT C3 to form alternative C5 CONVERTASE (C3BBB3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.
Complement activation initiated by the binding of COMPLEMENT C1 to ANTIGEN-ANTIBODY COMPLEXES at the COMPLEMENT C1Q subunit. This leads to the sequential activation of COMPLEMENT C1R and COMPLEMENT C1S subunits. Activated C1s cleaves COMPLEMENT C4 and COMPLEMENT C2 forming the membrane-bound classical C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.
A 150-kDa serum glycoprotein composed of three subunits with each encoded by a different gene (C8A; C8B; and C8G). This heterotrimer contains a disulfide-linked C8alpha-C8gamma heterodimer and a noncovalently associated C8beta chain. C8 is the next component to bind the C5-7 complex forming C5b-8 that binds COMPLEMENT C9 and acts as a catalyst in the polymerization of C9.
The first complement component to act in the activation of CLASSICAL COMPLEMENT PATHWAY. It is a calcium-dependent trimolecular complex made up of three subcomponents: COMPLEMENT C1Q; COMPLEMENT C1R; and COMPLEMENT C1S at 1:2:2 ratios. When the intact C1 binds to at least two antibodies (involving C1q), C1r and C1s are sequentially activated, leading to subsequent steps in the cascade of COMPLEMENT ACTIVATION.
Molecular sites on or in some B-lymphocytes and macrophages that recognize and combine with COMPLEMENT C3B. The primary structure of these receptors reveal that they contain transmembrane and cytoplasmic domains, with their extracellular portion composed entirely of thirty short consensus repeats each having 60 to 70 amino acids.
An important soluble regulator of the alternative pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It is a 139-kDa glycoprotein expressed by the liver and secreted into the blood. It binds to COMPLEMENT C3B and makes iC3b (inactivated complement 3b) susceptible to cleavage by COMPLEMENT FACTOR I. Complement factor H also inhibits the association of C3b with COMPLEMENT FACTOR B to form the C3bB proenzyme, and promotes the dissociation of Bb from the C3bBb complex (COMPLEMENT C3 CONVERTASE, ALTERNATIVE PATHWAY).
The larger fragment generated from the cleavage of C5 by C5 CONVERTASE that yields COMPLEMENT C5A and C5b (beta chain + alpha' chain, the residual alpha chain, bound by disulfide bond). C5b remains bound to the membrane and initiates the spontaneous assembly of the late complement components to form C5b-8-poly-C9, the MEMBRANE ATTACK COMPLEX.
The COOH-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S. It is a SERINE PROTEASE. C2a combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).
A G-protein-coupled receptor that signals an increase in intracellular calcium in response to the potent ANAPHYLATOXIN peptide COMPLEMENT C5A.
Enzymes that activate one or more COMPLEMENT PROTEINS in the complement system leading to the formation of the COMPLEMENT MEMBRANE ATTACK COMPLEX, an important response in host defense. They are enzymes in the various COMPLEMENT ACTIVATION pathways.
Compounds that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host.
A screening assay for circulating COMPLEMENT PROTEINS. Diluted SERUM samples are added to antibody-coated ERYTHROCYTES and the percentage of cell lysis is measured. The values are expressed by the so called CH50, in HEMOLYTIC COMPLEMENT units per milliliter, which is the dilution of serum required to lyse 50 percent of the erythrocytes in the assay.
Serum proteins that inhibit, antagonize, or inactivate COMPLEMENT C1 or its subunits.
Molecular sites on or in B-lymphocytes, follicular dendritic cells, lymphoid cells, and epithelial cells that recognize and combine with COMPLEMENT C3D. Human complement receptor 2 (CR2) serves as a receptor for both C3dg and the gp350/220 glycoprotein of HERPESVIRUS 4, HUMAN, and binds the monoclonal antibody OKB7, which blocks binding of both ligands to the receptor.
Serum peptides derived from certain cleaved COMPLEMENT PROTEINS during COMPLEMENT ACTIVATION. They induce smooth MUSCLE CONTRACTION; mast cell HISTAMINE RELEASE; PLATELET AGGREGATION; and act as mediators of the local inflammatory process. The order of anaphylatoxin activity from the strongest to the weakest is C5a, C3a, C4a, and C5a des-arginine.
Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.
A serum protein which is important in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. This enzyme cleaves the COMPLEMENT C3B-bound COMPLEMENT FACTOR B to form C3bBb which is ALTERNATIVE PATHWAY C3 CONVERTASE.
A plasma serine proteinase that cleaves the alpha-chains of C3b and C4b in the presence of the cofactors COMPLEMENT FACTOR H and C4-binding protein, respectively. It is a 66-kDa glycoprotein that converts C3b to inactivated C3b (iC3b) followed by the release of two fragments, C3c (150-kDa) and C3dg (41-kDa). It was formerly called KAF, C3bINF, or enzyme 3b inactivator.
A serum protein that regulates the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It binds as a cofactor to COMPLEMENT FACTOR I which then hydrolyzes the COMPLEMENT C4B in the CLASSICAL PATHWAY C3 CONVERTASE (C4bC2a).
Endogenous proteins that inhibit or inactivate COMPLEMENT C3B. They include COMPLEMENT FACTOR H and COMPLEMENT FACTOR I (C3b/C4b inactivator). They cleave or promote the cleavage of C3b into inactive fragments, and thus are important in the down-regulation of COMPLEMENT ACTIVATION and its cytolytic sequence.
GPI-linked membrane proteins broadly distributed among hematopoietic and non-hematopoietic cells. CD55 prevents the assembly of C3 CONVERTASE or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex.
Important enzymes in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.
The N-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S.
Small glycoproteins found on both hematopoietic and non-hematopoietic cells. CD59 restricts the cytolytic activity of homologous complement by binding to C8 and C9 and blocking the assembly of the membrane attack complex. (From Barclay et al., The Leukocyte Antigen FactsBook, 1993, p234)
Venoms from snakes of the genus Naja (family Elapidae). They contain many specific proteins that have cytotoxic, hemolytic, neurotoxic, and other properties. Like other elapid venoms, they are rich in enzymes. They include cobramines and cobralysins.
The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.
An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).
Important enzymes in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.
An endogenous 105-kDa plasma glycoprotein produced primarily by the LIVER and MONOCYTES. It inhibits a broad spectrum of proteases, including the COMPLEMENT C1R and the COMPLEMENT C1S proteases of the CLASSICAL COMPLEMENT PATHWAY, and the MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. C1-INH-deficient individuals suffer from HEREDITARY ANGIOEDEMA TYPES I AND II.
The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
A serine protease that is the complex of COMPLEMENT C3B and COMPLEMENT FACTOR BB. It cleaves multiple COMPLEMENT C3 into COMPLEMENT C3A (anaphylatoxin) and COMPLEMENT C3B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY.
A serine protease that cleaves multiple COMPLEMENT 5 into COMPLEMENT 5A (anaphylatoxin) and COMPLEMENT 5B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of CLASSICAL PATHWAY C3 CONVERTASE (C4b2a) with an additional COMPLEMENT C3B, or C4b2a3b.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A serine protease that cleaves multiple COMPLEMENT 3 into COMPLEMENT 3A (anaphylatoxin) and COMPLEMENT 3B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of COMPLEMENT 4B and COMPLEMENT 2A (C4b2a).
A ubiquitously expressed complement receptor that binds COMPLEMENT C3B and COMPLEMENT C4B and serves as a cofactor for their inactivation. CD46 also interacts with a wide variety of pathogens and mediates immune response.
Proteins that bind to particles and cells to increase susceptibility to PHAGOCYTOSIS, especially ANTIBODIES bound to EPITOPES that attach to FC RECEPTORS. COMPLEMENT C3B may also participate.
Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.
A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.
A serine protease that cleaves multiple COMPLEMENT C5 into COMPLEMENT C5A (anaphylatoxin) and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) with an additional COMPLEMENT C3B, or C3bBb3b.
The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Complement activation triggered by the interaction of microbial POLYSACCHARIDES with serum MANNOSE-BINDING LECTIN resulting in the activation of MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. As in the classical pathway, MASPs cleave COMPLEMENT C4 and COMPLEMENT C2 to form C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.
A 53-kDa protein that is a positive regulator of the alternate pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It stabilizes the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) and protects it from rapid inactivation, thus facilitating the cascade of COMPLEMENT ACTIVATION and the formation of MEMBRANE ATTACK COMPLEX. Individuals with mutation in the PFC gene exhibit properdin deficiency and have a high susceptibility to infections.
A derivative of complement C5a, generated when the carboxy-terminal ARGININE is removed by CARBOXYPEPTIDASE B present in normal human serum. C5a des-Arg shows complete loss of spasmogenic activity though it retains some chemotactic ability (CHEMOATTRACTANTS).
An adhesion-promoting leukocyte surface membrane heterodimer. The alpha subunit consists of the CD11b ANTIGEN and the beta subunit the CD18 ANTIGEN. The antigen, which is an integrin, functions both as a receptor for complement 3 and in cell-cell and cell-substrate adhesive interactions.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A cluster of convoluted capillaries beginning at each nephric tubule in the kidney and held together by connective tissue.
The clear portion of BLOOD that is left after BLOOD COAGULATION to remove BLOOD CELLS and clotting proteins.
Chronic glomerulonephritis characterized histologically by proliferation of MESANGIAL CELLS, increase in the MESANGIAL EXTRACELLULAR MATRIX, and a thickening of the glomerular capillary walls. This may appear as a primary disorder or secondary to other diseases including infections and autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Various subtypes are classified by their abnormal ultrastructures and immune deposits. Hypocomplementemia is a characteristic feature of all types of MPGN.
A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.
A genus of trematode flukes belonging to the family Schistosomatidae. There are over a dozen species. These parasites are found in man and other mammals. Snails are the intermediate hosts.
A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Inflammation of the renal glomeruli (KIDNEY GLOMERULUS) that can be classified by the type of glomerular injuries including antibody deposition, complement activation, cellular proliferation, and glomerulosclerosis. These structural and functional abnormalities usually lead to HEMATURIA; PROTEINURIA; HYPERTENSION; and RENAL INSUFFICIENCY.
Thickening of the walls of small ARTERIES or ARTERIOLES due to cell proliferation or HYALINE deposition.
Antibodies produced by a single clone of cells.
The genetic region which contains the loci of genes which determine the structure of the serologically defined (SD) and lymphocyte-defined (LD) TRANSPLANTATION ANTIGENS, genes which control the structure of the IMMUNE RESPONSE-ASSOCIATED ANTIGENS, HUMAN; the IMMUNE RESPONSE GENES which control the ability of an animal to respond immunologically to antigenic stimuli, and genes which determine the structure and/or level of the first four components of complement.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Established cell cultures that have the potential to propagate indefinitely.
The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
The natural bactericidal property of BLOOD due to normally occurring antibacterial substances such as beta lysin, leukin, etc. This activity needs to be distinguished from the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy, which is measured by a SERUM BACTERICIDAL TEST.
Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A specific mannose-binding member of the collectin family of lectins. It binds to carbohydrate groups on invading pathogens and plays a key role in the MANNOSE-BINDING LECTIN COMPLEMENT PATHWAY.
Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
Proteins prepared by recombinant DNA technology.
An IgG autoantibody against the ALTERNATIVE PATHWAY C3 CONVERTASE, found in serum of patients with MESANGIOCAPILLARY GLOMERULONEPHRITIS. The binding of this autoantibody to C3bBb stabilizes the enzyme thus reduces the actions of C3b inactivators (COMPLEMENT FACTOR H; COMPLEMENT FACTOR I). This abnormally stabilized enzyme induces a continuous COMPLEMENT ACTIVATION and generation of C3b thereby promoting the assembly of MEMBRANE ATTACK COMPLEX and cytolysis.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.
Plasma glycoproteins that form a stable complex with hemoglobin to aid the recycling of heme iron. They are encoded in man by a gene on the short arm of chromosome 16.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A biosensing technique in which biomolecules capable of binding to specific analytes or ligands are first immobilized on one side of a metallic film. Light is then focused on the opposite side of the film to excite the surface plasmons, that is, the oscillations of free electrons propagating along the film's surface. The refractive index of light reflecting off this surface is measured. When the immobilized biomolecules are bound by their ligands, an alteration in surface plasmons on the opposite side of the film is created which is directly proportional to the change in bound, or adsorbed, mass. Binding is measured by changes in the refractive index. The technique is used to study biomolecular interactions, such as antigen-antibody binding.
Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).
Glomerulonephritis associated with autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Lupus nephritis is histologically classified into 6 classes: class I - normal glomeruli, class II - pure mesangial alterations, class III - focal segmental glomerulonephritis, class IV - diffuse glomerulonephritis, class V - diffuse membranous glomerulonephritis, and class VI - advanced sclerosing glomerulonephritis (The World Health Organization classification 1982).
Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Plasmids containing at least one cos (cohesive-end site) of PHAGE LAMBDA. They are used as cloning vehicles.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Proteins found in any species of bacterium.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.
Transport proteins that carry specific substances in the blood or across cell membranes.
Serum serine proteases which participate in COMPLEMENT ACTIVATION. They are activated when complexed with the MANNOSE-BINDING LECTIN, therefore also known as Mannose-binding protein-Associated Serine Proteases (MASPs). They cleave COMPLEMENT C4 and COMPLEMENT C2 to form C4b2a, the CLASSICAL PATHWAY C3 CONVERTASE.
A group of inherited disorders of the ADRENAL GLANDS, caused by enzyme defects in the synthesis of cortisol (HYDROCORTISONE) and/or ALDOSTERONE leading to accumulation of precursors for ANDROGENS. Depending on the hormone imbalance, congenital adrenal hyperplasia can be classified as salt-wasting, hypertensive, virilizing, or feminizing. Defects in STEROID 21-HYDROXYLASE; STEROID 11-BETA-HYDROXYLASE; STEROID 17-ALPHA-HYDROXYLASE; 3-beta-hydroxysteroid dehydrogenase (3-HYDROXYSTEROID DEHYDROGENASES); TESTOSTERONE 5-ALPHA-REDUCTASE; or steroidogenic acute regulatory protein; among others, underlie these disorders.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
An individual in which both alleles at a given locus are identical.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
Biologically active substances whose activities affect or play a role in the functioning of the immune system.
Elements of limited time intervals, contributing to particular results or situations.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
The number of copies of a given gene present in the cell of an organism. An increase in gene dosage (by GENE DUPLICATION for example) can result in higher levels of gene product formation. GENE DOSAGE COMPENSATION mechanisms result in adjustments to the level GENE EXPRESSION when there are changes or differences in gene dosage.
The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.
Glycoproteins found on the membrane or surface of cells.
The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.
The sum of the weight of all the atoms in a molecule.
The rate dynamics in chemical or physical systems.
Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.
The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.
Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.
The presence of proteins in the urine, an indicator of KIDNEY DISEASES.
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.
Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.
A gram-positive organism found in the upper respiratory tract, inflammatory exudates, and various body fluids of normal and/or diseased humans and, rarely, domestic animals.
A class of C-type lectins that target the carbohydrate structures found on invading pathogens. Binding of collectins to microorganisms results in their agglutination and enhanced clearance. Collectins form trimers that may assemble into larger oligomers. Each collectin polypeptide chain consists of four regions: a relatively short N-terminal region, a collagen-like region, an alpha-helical coiled-coil region, and carbohydrate-binding region.
Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.
A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
A plasma protein that circulates in increased amounts during inflammation and after tissue damage.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)
Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.
Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.
A method (first developed by E.M. Southern) for detection of DNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.
Degenerative changes in the RETINA usually of older adults which results in a loss of vision in the center of the visual field (the MACULA LUTEA) because of damage to the retina. It occurs in dry and wet forms.
A constitution or condition of the body which makes the tissues react in special ways to certain extrinsic stimuli and thus tends to make the individual more than usually susceptible to certain diseases.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.
Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.
The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
A method for the detection of very small quantities of antibody in which the antigen-antibody-complement complex adheres to indicator cells, usually primate erythrocytes or nonprimate blood platelets. The reaction is dependent on the number of bound C3 molecules on the C3b receptor sites of the indicator cell.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
A technique that combines protein electrophoresis and double immunodiffusion. In this procedure proteins are first separated by gel electrophoresis (usually agarose), then made visible by immunodiffusion of specific antibodies. A distinct elliptical precipitin arc results for each protein detectable by the antisera.
Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.
Immunoglobulins produced in a response to BACTERIAL ANTIGENS.
The systematic study of the complete complement of proteins (PROTEOME) of organisms.
Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.
A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
A large collection of DNA fragments cloned (CLONING, MOLECULAR) from a given organism, tissue, organ, or cell type. It may contain complete genomic sequences (GENOMIC LIBRARY) or complementary DNA sequences, the latter being formed from messenger RNA and lacking intron sequences.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.
A condition characterized by the recurrence of HEMOGLOBINURIA caused by intravascular HEMOLYSIS. In cases occurring upon cold exposure (paroxysmal cold hemoglobinuria), usually after infections, there is a circulating antibody which is also a cold hemolysin. In cases occurring during or after sleep (paroxysmal nocturnal hemoglobinuria), the clonal hematopoietic stem cells exhibit a global deficiency of cell membrane proteins.
A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.
Group of diseases mediated by the deposition of large soluble complexes of antigen and antibody with resultant damage to tissue. Besides SERUM SICKNESS and the ARTHUS REACTION, evidence supports a pathogenic role for immune complexes in many other IMMUNE SYSTEM DISEASES including GLOMERULONEPHRITIS, systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC) and POLYARTERITIS NODOSA.

Nuclear phosphoinositide 3-kinase C2beta activation during G2/M phase of the cell cycle in HL-60 cells. (1/5)

The activity of nuclear phosphoinositide 3-kinase C2beta (PI3K-C2beta) was investigated in HL-60 cells blocked by aphidicolin at G(1)/S boundary and allowed to progress synchronously through the cell cycle. The activity of immunoprecipitated PI3K-C2beta in the nuclei and nuclear envelopes showed peak activity at 8 h after release from the G(1)/S block, which correlates with G(2)/M phase of the cell cycle. In the nuclei and nuclear envelopes isolated from HL-60 cells at 8 h after release from G(1)/S block, a significant increase in the level of incorporation of radiolabeled phosphate into phosphatidylinositol 3-phosphate (PtdIns(3)P) was observed with no change in the level of radiolabeled PtdIns(4)P, PtdIns(4,5)P(2) and PtdIns(3,4,5)P(3). On Western blots, PI3K-C2beta revealed a single immunoreactive band of 180 kDa, whereas in the nuclei and nuclear envelopes isolated at 8 h after release, the gel shift of 18 kDa was observed. When nuclear envelopes were treated for 20 min with mu-calpain in vitro, the similar gel shift and increase in PI3K-C2beta activity was observed which was completely inhibited by pretreatment with calpain inhibitor calpeptin. The presence of PI3K inhibitor LY 294002 completely abolished the calpain-mediated increase in the activity of PI3K-C2beta but did not prevent the gel shift. When HL-60 cells were released from G(1)/S block in the presence of either calpeptin or LY 294002, the activation of nuclear PI3K-C2beta was completely inhibited. These results demonstrate the calpain-mediated activation of the nuclear PI3K-C2beta during G(2)/M phase of the cell cycle in HL-60 cells.  (+info)

The structure of C2b, a fragment of complement component C2 produced during C3 convertase formation. (2/5)

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Postsynaptic regulation of synaptic plasticity by synaptotagmin 4 requires both C2 domains. (3/5)

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Effect of sodium chloride concentration on fluid-phase assembly and stability of the C3 convertase of the classical pathway of the complement system. (4/5)

The assembly of the classical-pathway C3 convertase from C4 and I2-treated C2 by the action of C1s is an Mg2(+)-dependent reaction. The Mg2+ concentration necessary for the assembly of C3 convertase in the fluid phase was found to be dependent on NaCl concentration. In the absence of NaCl more than 5 mM-MgCl2 was found to be required, whereas 0.5 mM-MgCl2 was adequate for the assembly of C3 convertase in the presence of 150 mM-NaCl. The C3 convertase assembled in a low-ionic-strength buffer was extremely labile compared with that assembled in buffer of physiological ionic strength, and the stability of C3 convertase was improved with the increase in NaCl concentration. It was found that the stabilizing effect of NaCl on C3 convertase was due to inhibition of the dissociating activity of C2b, which was formed during the assembly of C3 convertase. In addition to the dissociation-accelerating effect, C2b inhibited the assembly of C3 convertase in low-ionic-strength buffer, and this effect also was diminished with increase in NaCl concentration. An increase in NaCl concentration to more than 200 mM resulted in a decrease in the assembly of C3 convertase. This effect was not due to the lability of the assembled C3 convertase but due rather to the inhibition of C2 cleavage by C1s. Purified C3 convertase itself is stable in dilute medium or high-ionic-strength medium such as 500 mM-NaCl, suggesting that the interactions between C4b and C2a are hydrophobic. In these respects C2b seemed to be functionally similar to C4bp, but C2b failed to act as a cofactor for the Factor I-catalysed C4b cleavage.  (+info)

Purification and characterization of the C3 convertase of the classical pathway of human complement system by size exclusion high-performance liquid chromatography. (5/5)

The C3 convertase of the classical pathway of the complement system is a liable complex, C4b,2a, and is activated by limited proteolysis of two components, C4 and C2, by C1s. By utilizing iodine-treated C2 and size exclusion high-performance liquid chromatography (HPLC), we have succeeded in isolating for the first time the classical pathway C3 convertase. Size exclusion HPLC demonstrated that the apparent molecular mass of the C3 convertase was 280K daltons. The C3 convertase decay-dissociates spontaneously into C4b and C2a. The decay-dissociation is a temperature-dependent reaction and the half-lives of the C3 convertase at 24, 30, and 37 degrees C were estimated to be 400, 180, and 60 min, respectively. The decay-dissociation was also dependent on pH and was accelerated by increasing pH. In addition, the decay-dissociation of the C3 convertase was accelerated by C2b. This result suggests that C2b acts as a feedback inhibitor on the activation of the classical pathway of complement system.  (+info)

No data available that match "complement c2b"


The complement component C5 can be also activated by fluid phase C5 convertase. C5 is activated by CVFBb in the presence of ... The modified C5 convertase, C4b2boxy3b, contains C2b that is derived from C2 oxidized by iodine. The target of C5 convertase is ... In these respects, the mode of action of C5 is completely analogous to that of the other components of complement. The C5 step ... The binding of C5 is influenced by C6 and C7, components which are thought to act subsequent to it in the complement sequence. ...
The C1 complex (complement component 1, C1) is a protein complex involved in the complement system. It is the first component ... Active C1s splits C4 and then C2, producing C4a, C4b, C2a and C2b. The classical pathway C3-convertase (C4bC2b complex) is ... 2001). "The complement system and innate immunity". Immunobiology: The Immune System in Health and Disease. New York: Garland ... The antibodies IgM or certain subclasses of IgG complexed with antigens are able to initiate the complement system: a single ...
DAF protects host cells from damage by autologous complement. DAF acts on C2b and Bb and dissociates them rapidly from C4b and ... The C3 convertase formed in the classical or lectin pathways is formed of C4b and C2b instead (NB: C2b, the larger fragment of ... Cleavage of complement C3 by a free floating convertase, thrombin, plasmin or even a bacterial enzyme leads to formation of C3a ... The larger C2b produced by C2 hydrolysis attaches to the C4b to form the classical C3 convertase, C4b2b (formerly called C4b2a ...
Complement receptors, collectins, ficolins, pentraxins such as serum amyloid and C-reactive protein, lipid transferases, ... binding of C2 causes release of C2b. Together, MBL, C4b and C2a are known as the C3 convertase. C3 is cleaved into its a and b ... Once bound to the ligands MBL and Ficolin oligomers recruit MASP1 and MASP2 and initiate the lectin pathway of complement ... "/"self turned nonself" type pathogen pattern are also identified and destroyed (e.g. by complement fixation or other cytotoxic ...
Complement decay-accelerating factor, also known as CD55 or DAF, is a protein that, in humans, is encoded by the CD55 gene. DAF ... Interaction of DAF with cell-associated C4b of the classical and lectin pathways interferes with the conversion of C2 to C2b, ... DAF contains four complement control protein (CCP) repeats with a single N-linked glycan positioned between CCP1 and CCP2. CCP2 ... Binding of DAF to human HIV-1 when the virons are budding from the surface of infected cells may protect HIV-1 from complement ...
MASP-2 is activated to cleave complement components C4 and C2 into C4a, C4b, C2a, and C2b. MASP1 (protein) Mannan-binding ... MASP-2 is involved in the complement system. MASP-2 is very similar to the C1s molecule, of the classical complement pathway, ... The Ra-reactive factor (RARF) is a complement-dependent bactericidal factor that binds to the Ra and R2 polysaccharides ... Petersen SV, Thiel S, Jensenius JC (2001). "The mannan-binding lectin pathway of complement activation: biology and disease ...
... and C2b (historically, the larger fragment of C2 was called C2a but is now referred to as C2b). C4b and C2b bind to form the ... Polymorphisms of complement component 3, complement factor B, and complement factor I, as well as deletion of complement factor ... The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability ... Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway ...
... and C2b). C4a and C2b form C4bC2b, also known as C3 convertase. The lectin pathway is activated when pattern-recognition ... 12th European Meeting on Complement in Human Disease12th European Meeting on CHD12th European Meeting on Complement in Human ... C3a is one of the proteins formed by the cleavage of complement component 3; the other is C3b. C3a is a 77 residue ... Anaphylatoxins are small complement peptides that induce proinflammatory responses in tissues. C3a is primarily regarded for ...
"Entrez Gene: C2 complement component 2". Krishnan V, Xu Y, Macon K, Volanakis JE, Narayana SV (2009). "The structure of C2b, a ... Complement C2 is a protein that in humans is encoded by the C2 gene. The protein encoded by this gene is part of the classical ... C2b is the smallest , enzymatically active fragment which is incorporated into the C3 convertase in this pathway, C4b2b (NB: ... It is thought that cleavage of C2 by C1s, while bound to C4b, results in a conformational rotation of C2b whereas the released ...
It interacts with protein C2; the same protease invoked earlier, C1s, then cleaves C2 into two parts, termed C2a and C2b, with ... Complement component 4A Complement component 4B HLA A1-B8-DR3-DQ2 haplotype Complement system Complement deficiency Sekar A, ... Complement component 4 (C4), in humans, is a protein involved in the intricate complement system, originating from the human ... All three pathways converge at a step in which complement protein C3 is cleaved into proteins C3a and C3b, which results in a ...
The activated C1s cleaves C4 into C4a and C4b, and C2 into C2a and C2b. The larger fragments C4b and C2b form C4b2b (according ... Alternative complement pathway - another complement system pathway Lectin pathway - another complement system pathway Noris, ... The classical complement pathway is one of three pathways which activate the complement system, which is part of the immune ... Activation of the complement pathway through the classical, lectin or alternative complement pathway is followed by a cascade ...
... complement c2 MeSH D12.776.124.486.274.150.500 - complement c2a MeSH D12.776.124.486.274.150.750 - complement c2b MeSH D12.776. ... complement c1 MeSH D12.776.124.486.274.050.270 - complement c1q MeSH D12.776.124.486.274.050.280 - complement c1r MeSH D12.776. ... complement c3c MeSH D12.776.124.486.274.250.260.750 - complement c3d MeSH D12.776.124.486.274.350 - complement c4 MeSH D12.776. ... complement c5b MeSH D12.776.124.486.274.550 - complement c6 MeSH D12.776.124.486.274.650 - complement c7 MeSH D12.776.124.486. ...
MASP-1 and MASP-2 are activated to cleave complement components C4 and C2 into C4a, C4b, C2a, and C2b. In f, two smaller MBL- ... C4a and C2b act as potent cytokines, with C4a causing degranulation of mast cells and basophils and C2b acting to increase ... The lectin pathway or lectin complement pathway is a type of cascade reaction in the complement system, similar in structure to ... Additional resources on Endothelial Injury Syndrome Classical complement pathway Alternative complement pathway Mannan-binding ...
... and C2b. C4b and C2b (historically, the larger fragment of C2 was called C2a but is now referred to as C2b) bind to form the ... complement factor B, and complement factor I, as well as deletion of complement factor H-related 3 and complement factor H- ... Complement deficiencyEdit. Main article: Complement deficiency. It is thought that the complement system might play a role in ... Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway ...
The C1 complement complex binds to these antibodies resulting in its activation via cross proteolysis. This activated C1 ... or a C5 convertase when bound to C4b and C2b (C4b2b3b complex) or when an additional C3b molecule binds to the C3bBb complex ( ... C3b is the larger of two elements formed by the cleavage of complement component 3, and is considered an important part of the ... The key to the success of the complement system in clearing antigens is regulating the effects of C3b to pathogens alone and ...
Haplogroup C2b is so rare that it was proposed to represent a post 6000 years arrival to the continent - a hypothesis disproved ... the emerging picture is of a typical early Archaic economy structured around staple carbohydrates complemented by hunting of ... Four individuals have the Q1a2a Y-chromosome haplogrpup and one individual the C2b Y-chromosome haplogroup. The former and ...
Zipfel, P. F., Hallström, T., & Riesbeck, K. (2013). Human complement control and complement evasion by pathogenic microbes- ... C2b, C4a ja C4b. C2a ja C4b kombineeruvad ning moodustub C3-konvertaas C4bC2a. Sama konvertaasi moodustumine on omane ka ... 1,0 1,1 1,2 1,3 Rus, H., Cudrici, C., & Niculescu, F. (2005). The role of the complement system in innate immunity. Immunologic ... 7,0 7,1 Lambris, J. D., Ricklin, D., & Geisbrecht, B. V. (2008). Complement evasion by human pathogens. Nature Reviews. ...
By definition, the semistable locus X s s {\displaystyle X^{ss}} is the complement of the zero set V ( R + G ) {\displaystyle V ... c&-2b&a\end{bmatrix}}} hence the only point where the differential and the polynomial f {\displaystyle f} both vanish is at the ...
C2b and C2a. C2a, a serine protease, then combines with complement factor C4b to generate the C3 or C5 convertase. ... Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two ... R-MMU-166663 Initial triggering of complement. R-MMU-174577 Activation of C3 and C5. R-MMU-977606 Regulation of Complement ... R-MMU-166663 Initial triggering of complement. R-MMU-174577 Activation of C3 and C5. R-MMU-977606 Regulation of Complement ...
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5) C1 cleaves C2 C2a +C2b. 6) C3 convertase (C4b2a) splits C3 into C3a+C3b (important part: where converges). I) C3b ( ... Cannot tell cells apart, only groups/types (gram+/-) all have same gene to recognize patterns, same complement of receptors ( ... What are the three pathways to activate the complement system? What does each need to start? ... 1)recognition by tissue macrophages and complement. 2) macrophage cytokines production (tissue cell sentries). 3) other cells ...
Complement C2, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene ... complement component 2,110kDa,activated by C1r to form C2a and C2b,combining with C4A and C4B to form C3/C5 convertase, ... Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or ... Complement component 2 (A2BE06_HUMAN). *cDNA FLJ38939 fis, clone NT2NE2015747, highly similar to COMPLEMENT C2 (EC 3.4.21.43) ( ...
The enzymatic fragment of C2 is referred to as C2b in this review; the same fragment is sometimes designated as C2a in ... Complement beyond microbial defense. The past decade revealed a new perception of complement that reaches beyond the ... Complement can also be therapeutically engaged for the killing of tumor cells via complement-dependent cytotoxicity; for ... Beneficial effects of complement inhibition with soluble complement receptor 1 (TP10) during cardiac surgery: is there a gender ...
The origin and evolution of the complement system. *The evolution of complement begins with an ancestor to protease inhibitor a ... C2 can then attach to C4b, and is then cleaved by C1 into C2a and C2b. C2b and C4b then form the second serine protease in the ... Model for the evolution of the complement system Any model for the origin of the complement system must begin with the ... The complement system - Behes largest error in chapter 6 is choosing the complement system as an example of how evolution ...
... complement protein homologous to complement C3 of the mammalian complement system." Journal of Immunology 133(6): 3242-3249. ... C2 can then attach to C4b, and is then cleaved by C1 into C2a and C2b. C2b and C4b then form the second serine protease in the ... The origin and evolution of the complement system. *The evolution of complement begins with an ancestor to protease inhibitor a ... Model for the evolution of the complement system Any model for the origin of the complement system must begin with the ...
Complement cascade (Homo sapiens) * Initial triggering of complement (Homo sapiens) * Conversion of C2 into C2a and C2b (Homo ... Lectin pathway of complement activation (Homo sapiens) * Activation of MASPs (Homo sapiens) * MBL2,FCN:activated MASPs: ...
Complement cascade (Homo sapiens) * Initial triggering of complement (Homo sapiens) * Conversion of C2 into C2a and C2b (Homo ... Classical antibody-mediated complement activation (Homo sapiens) * Activation of C1r (Homo sapiens) * Antigen:IgG:C1Q:2x ... Regulation of Complement cascade (Homo sapiens) * Antigen:IgG:C1Q:2xActivated C1R:SERPING1:2xActivated C1S:SERPING1 dissociates ...
"Entrez Gene: C2 complement component 2". Krishnan V, Xu Y, Macon K, Volanakis JE, Narayana SV (2009). "The structure of C2b, a ... Complement C2 is a protein that in humans is encoded by the C2 gene. The protein encoded by this gene is part of the classical ... C2b is the smallest , enzymatically active fragment which is incorporated into the C3 convertase in this pathway, C4b2b (NB: ... It is thought that cleavage of C2 by C1s, while bound to C4b, results in a conformational rotation of C2b whereas the released ...
The complement component C5 can be also activated by fluid phase C5 convertase. C5 is activated by CVFBb in the presence of ... The modified C5 convertase, C4b2boxy3b, contains C2b that is derived from C2 oxidized by iodine. The target of C5 convertase is ... In these respects, the mode of action of C5 is completely analogous to that of the other components of complement. The C5 step ... The binding of C5 is influenced by C6 and C7, components which are thought to act subsequent to it in the complement sequence. ...
The complement system is a key component of the innate immune system that is involved in eliminating unwanted self and nonself ... The release of soluble mediators (C4a, C2b, C3a, Ba, C5a) is indicated with small arrows. Activator‐bound complement components ... Schneider PM and Rittner C (1997) Complement genetics. In: Dodds AW, Sim RB (eds.) Complement. A Practical Approach, pp. 165- ... The complement system is a key component of the innate immune system that is involved in eliminating unwanted self and nonself ...
... complement component 2) for ICC/IF, WB. Anti-Complement C2 pAb (GTX105404) is tested in Human samples. 100% Ab-Assurance. ... Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or ... CO2 antibody, DKFZp779M0311 antibody, C2 antibody, complement C2 antibody, complement component C2 antibody, C3/C5 convertase ... complement component 2. Background. Component C2 is a serum glycoprotein that functions as part of the classical pathway of the ...
... and C2b. C4b and C2b (historically, the larger fragment of C2 was called C2a but is now referred to as C2b) bind to form the ... complement factor B, and complement factor I, as well as deletion of complement factor H-related 3 and complement factor H- ... Complement deficiencyEdit. Main article: Complement deficiency. It is thought that the complement system might play a role in ... Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway ...
Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or ... Component C2 is a serum glycoprotein that functions as part of the classical pathway of the complement system. ...
Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or ... Component C2 is a serum glycoprotein that functions as part of the classical pathway of the complement system. ...
The C2 gene provides instructions for making the complement component 2 protein. Learn about this gene and related health ... The structure of C2b, a fragment of complement component C2 produced during C3 convertase formation. Acta Crystallogr D Biol ... Complement component 2 deficiency. At least five mutations in the C2 gene have been found to cause complement component 2 ... This protein helps regulate a part of the bodys immune response known as the complement system. The complement system is a ...
Complement System. The complement system is an important part of the immune system. It consists of more than 22 proteins, which ... A vasoactive peptide generated by cleavage of the C2b fragment by plasmin. Early HAE research postulated that a C2 kinin may be ... The complement system is involved in blocking pathogens like bacteria or fungi. However, it can also damage tissues if it gets ... Quantitative levels of the fourth component of complement.. Cetor®. Brand name of the C1-Inhibitor Concentrate marketed by ...
Then they cleave C1s (another serine protease). The C1-complex now binds to and splits C2 and C4, producing C2b (used to be ... Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway ... Main article: Complement deficiency. It is thought that the complement system might play a role in many diseases with an immune ... Regulation of the Complement System. The complement system has the potential to be extremely damaging to host tissues meaning ...
Initial triggering of complement (Danio rerio) * Conversion of C2 into C2a and C2b (Danio rerio) * Homologues of C2a [ ... Complement cascade (Danio rerio) * Activation of C3 and C5 (Danio rerio) * Activation of C5 (Danio rerio) * C4b:C2a:C3b [plasma ...
ELISA for the measurement of Human Complement C2 in Human Cell culture supernatant, Saliva, Milk, Serum, Plasma, Cerebral ... Human Complement C2 ELISA Kit is a Sandwich (quantitative) ... C2b and C2a. C2a, a serine protease, then combines with ... Defects in C2 are the cause of complement component 2 deficiency (C2D) [MIM:217000]. A deficiency of the complement classical ... Cynomolgus C2 detected with complement C2 human ELISA kit (ab154132). Average Good 4/5 (Ease of Use) ...
C2b and C2a. C2a, a serine protease, then combines with complement factor 4b to generate the C3 or C5 convertase. ... Defects in C2 are the cause of complement component 2 deficiency (C2D) [MIM:217000]. A deficiency of the complement classical ... No se ha testado si el anticuerpo reacciona con el fragmento C2b en su forma purificada. Espero haberte ayudado. Para cualquier ... Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two ...
The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by ... The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by ... In this context, the complement, as one of the first line of host defense against infection was shown to play an important role ... Nevertheless, the parasite uses a sequence of events in order to escape from complement-mediated lysis. In fact, several T. ...
1.4.3.3 Complement inhibition. S. aureus is now recognized as a master of complement evasion. Unlike other bacteria which use ... In the presence of SCIN, the deposition of C3b and MAC were prevented, so was the C2b and Ba release. However the amount of ... The human complement system is discussed in more detail below. One outcome of complement activation is the production of ... The list of anti-complement virulence factors is growing. So far, five complement inhibitors have been demonstrated and well ...
The reduced staining in sytAD1 can be attributed in part to the loss of missing epitopes in the C2B domain, since the ... This observation is consistent with the fact that the AD3 allele is homozygous lethal but complements another mutant phenotype ... However, little is known as to why a missense mutation (Tyr-334-Asn) disrupts the function of the C2B domain at the molecular ... Loewen, C.A., Lee, S. M., Shin, Y. K. and Reist, N. E. (2006). C2B polylysine motif of synaptotagmin facilitates a Ca2+- ...
Initial triggering of complement (Homo sapiens) * Conversion of C2 into C2a and C2b (Homo sapiens) * C2a [extracellular region ... Complement cascade (Homo sapiens) * Activation of C3 and C5 (Homo sapiens) * Activation of C5 (Homo sapiens) * C5 convertases [ ... Regulation of Complement cascade (Homo sapiens) * C3 convertases spontaneously dissociate (Homo sapiens) * C2a [extracellular ...
Complement at Cram.com. Quickly memorize the terms, phrases and much more. Cram.com makes it easy to get the grade you want! ... C2b a weak kinin, and so can increase vascular permeability, it is a proteolytic fragment of C2 ... term which refers to the spontaneous production of C3b which will activate AP of complement ... ":"Immuno Five: Complement","payreferer_url":"\/flashcards\/copy\/immuno-five-complement-503728","isGuest":true,"ga_id":"UA- ...
Complement component C2b (substance). Code System Preferred Concept Name. Complement component C2b (substance). ... Complement component fragment (substance) {78036008 , SNOMED-CT } Complement component, classic pathway (substance) {67899004 ...
  • C2a, a serine protease, then combines with complement factor C4b to generate the C3 or C5 convertase. (uniprot.org)
  • This results in inhibition of the classical and lectin pathway of complement activation, probably due to interference with binding of C2a to C4b such that C3 convertase cannot be formed. (genecards.org)
  • C2b is the smallest , enzymatically active fragment which is incorporated into the C3 convertase in this pathway, C4b2b (NB: some sources now refer to the larger fragment of C2 as C2b, making the C3 convertase C4b2b, whereas older sources refer to the larger fragment of C2 as C2a, making the C3 convertase C4b2a). (wikipedia.org)
  • This complex might interact with another C3b and thus form the alternative pathway C5 convertase.CVFBb is a noncovalent association product of CVF3 and the complement fragment Bb. (wikipedia.org)
  • The modified C5 convertase, C4b2boxy3b, contains C2b that is derived from C2 oxidized by iodine. (wikipedia.org)
  • The target of C5 convertase is complement protein C5. (wikipedia.org)
  • The complement component C5 can be also activated by fluid phase C5 convertase. (wikipedia.org)
  • Together, these proteins form a complex called C3 convertase, which triggers further activation of the pathway, allowing the proteins of the complement system to participate in an immune response. (medlineplus.gov)
  • Without this protein to form C3 convertase, activation of the complement system is stalled. (medlineplus.gov)
  • In fact, several T. cruzi molecules are known to interfere in the initiation of all three pathways and in the assembly of C3 convertase, a key step in the activation of complement. (frontiersin.org)
  • Moreover, T. cruzi promotes secretion of plasma membrane-derived vesicles from host cells, which prevent the activity of C3 convertase C4b2a and thereby may hinder complement. (frontiersin.org)
  • C4b and C2b form the C3 convertase b. (wikidot.com)
  • C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. (bireme.br)
  • C5 convertase is also formed by the classical pathway when C3b binds C4b and C2b. (rhein-main-verzeichnis.info)
  • The crystal structure of C2a, the catalytic fragment of classical pathway C3 and C5 convertase of human complement. (uab.edu)
  • C5 convertase, generated by the alternative, classical, or lectin pathway, initiates the activation of late components of the complement system to form membrane attack complex (MAC) and ultimately kills the pathogen. (microbeonline.com)
  • C4b and C2a combine on the surface of the pathogen to form C3-convertase (C4b and C2a), while C4a and C2b act as chemoattractants. (meddic.jp)
  • The end result of this complement activation or complement fixation cascade is stimulation of phagocytes to clear foreign and damaged material, inflammation to attract additional phagocytes, and activation of the cell-killing membrane attack complex . (wikipedia.org)
  • The complement system is a biochemical cascade which helps clear pathogens from an organism. (wikidoc.org)
  • The 'complement cascade' is constitutive and non-specific but it must be activated in order to function. (atwebpages.com)
  • Once initiated, a cascade of events (the 'complement cascade') ensues, providing the functions listed above. (atwebpages.com)
  • 3. Describe the Alternative Pathway of the complement cascade if it was NOT activated by random cleavage on the surface of a microbe. (wikidot.com)
  • It is a triggered enzyme cascade and there are more than 20 different proteins in the complement cascades, with most being enzymes or pro-enzymes. (vetbook.org)
  • The binding of antibodies (IgG or IgM) to the antigens which are mainly bacteria ( i.e antigen-antibody complex) trigger the activation of complement proteins, mainly: C1 and C4 and subsequently lead to the activation of other complement proteins in a cascade reaction. (atgventure.com)
  • A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. (bireme.br)
  • The complement system or complement cascade as it is also known is a complex system of multiple proteins involved in inflammation and immunological response. (vetsci.co.uk)
  • The complement system is known as a cascade because of the triggering and amplification of further components of the system. (vetsci.co.uk)
  • The whole complement cascade can be triggered in its entirety in a matter of microseconds. (vetsci.co.uk)
  • During the activation process the smaller 'a' subcomponent peptides which are formed, mediate many of the other effects caused by the complement cascade, for example acting as chemoattractants. (vetsci.co.uk)
  • There are three types of complement cascade, the classical and alternative pathways and the Mannan-binding lectin pathway. (vetsci.co.uk)
  • However in the alternative pathway the complement cascade does not require that an antibody binds to the antigen. (vetsci.co.uk)
  • Reaction Cascade of the Complement System: Classical complement pathway The classical and alternative complement pathways The classical pathway is triggered by activation of the C1-complex. (rhein-main-verzeichnis.info)
  • Circulating IgM, however, exists as a planar configuration in which the Clq-binding sites are not exposed (Figure 13-4, on page 302) and therefore cannot activate the complement cascade. (78stepshealth.us)
  • Diagram of the complement cascade, which consists of enzymatic steps involving a number of inactive proenzymes (or zymogens). (asmscience.org)
  • Referral to a third function, complement components cascade fragment c2b binds c5b man ah, pillai s: Cellular and molecular immunology, ed 7 [updated edition], philadelphia, 2006, saunders. (wisc.edu)
  • Disrupts osmotic stability and lyses bacteria, virus, or cells that are infected or damaged MAC Pores Summary of Complement Functions In addition to providing protection from pathogens, complement plays an Important role in normal physiology by removing apoptotic and damaged cells and cell debris How is Complement Cascade Initiated? (slidegur.com)
  • The lectin pathway is a type of cascade reaction in the complement system, similar in structure to the classical complement pathway, [ 1 ] in that, after activation, it proceeds through the action of C4 and C2 to produce activated complement proteins further down the cascade. (meddic.jp)
  • Mannan-binding lectin (MBL, also called mannose-binding protein) is a protein belonging to the collectin family that is produced by the liver and can initiate the complement cascade by binding to pathogen surfaces. (meddic.jp)
  • Complement receptors and Fc receptors, expressed on effector cells, have a synergistic role in antibody‐mediated immune modulation and antigen clearance. (els.net)
  • Immunofluorescence analysis of methanol-fixed A431, using Complement C2(GTX105404) antibody at 1:200 dilution. (genetex.com)
  • The classical complement pathway typically requires antigen-antibody complexes for activation (specific immune response), whereas the alternative pathway can be activated by spontaneous C3 hydrolysis, foreign material, pathogens, or damaged cells. (wikipedia.org)
  • A Complement C2 specific antibody has been precoated onto 96-well plates and blocked. (abcam.com)
  • Standards or test samples are added to the wells and subsequently a Complement C2 specific biotinylated detection antibody is added and then followed by washing with wash buffer. (abcam.com)
  • Cell debris, virus, bacteria, antibody-antigen complexes and more items are not protected by these proteins and are subject to the complement system. (iahealth.net)
  • The binding of antibody to its antigen triggers the complement system through the so-called classical pathway. (periobasics.com)
  • Complement, an important aspect of porcine immunology , is so called because it complements the function of antibody. (vetbook.org)
  • Complement activation by the classical pathway commonly begins with the formation of soluble antigen-antibody complexe s ( immune complexes ) or with the binding of antibody to antigen on a suitable target, such as a bacterial cell . (78stepshealth.us)
  • The formation of an antigen-antibody complex induces conformational changes in the Fc portion of the IgM molecule that expose a binding site for the C1 component of the complement system . (78stepshealth.us)
  • Complement activation is triggered by an antibody when it is bound to the antigen. (microbeonline.com)
  • Hence, the antibody activates the complement system only when bound to an antigen. (microbeonline.com)
  • In 1899, Paul Ehrlich renamed the heat sensitive component complement defining it as "the activity of blood serum that completes the action of antibody. (microbeonline.com)
  • The first category encompasses the complement serum proteins, which react with foreign bodies in either an antibody-dependent or antibody-independent manner. (asmscience.org)
  • Host phagocytes, such as neutrophils and macrophages, have receptor proteins on their cell surfaces that specifically recognize portions of the antibody molecule (Fc receptors), fragments of complement (C3 receptors), and fibronectin. (asmscience.org)
  • In contrast to the classical complement pathway, the lectin pathway does not recognize an antibody bound to its target. (meddic.jp)
  • Complement C4c, anti_human antibody storage GENTAUR recommends for long therm storage to freeze at -24 C. For short time storage up to 30 days we suggest fridge storage at 1 to 10 C. Prevent multiple freeze taw cycles of Complement C4c, anti_human. (antibody-antibodies.com)
  • Complement C2 antibody LS-C722609 is a PE-conjugated rabbit polyclonal antibody to human Complement C2. (lsbio.com)
  • Complement C2 antibody was raised against recombinant C2 (Ile245-His451) expressed in E. coli. (lsbio.com)
  • Complement C2 antibody LS-C442556 is an FITC-conjugated rabbit polyclonal antibody to Complement C2 from human, mouse, rat and other species. (lsbio.com)
  • Complement C2 antibody was raised against synthetic peptide located between aa201-250 of human C2 (P06681, NP_000054). (lsbio.com)
  • It is thought that cleavage of C2 by C1s, while bound to C4b, results in a conformational rotation of C2b whereas the released C2a fragment may retain most of its original structure. (wikipedia.org)
  • The smaller fragment, C2a (or C2b, depending on the source) is released into the fluid phase. (wikipedia.org)
  • Cleavage of C5 requires complement fragment C3b which binds C5 and renders it susceptible to cleavage by the C4b,2a complex. (qmul.ac.uk)
  • The large fragment formed when COMPLEMENT C4 is cleaved by COMPLEMENT C1S. (labome.org)
  • The COOH-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S. (bireme.br)
  • The proteolytic cleavage of C5 is the only known enzymatic event in assembly of the cytolytic membrane attack complex of complement. (wikipedia.org)
  • Complement proteins such as C5b, C6, C7 and C8 and C9 assembles at the membrane of cells to form "Membrane-attack complex (MAC)" which creates pores on the membrane of target cells and subsequently leading to their disruption. (atgventure.com)
  • Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. (bireme.br)
  • These are the terminal complement components that form the membrane-attack complex. (wordpress.com)
  • Once activated, several relevant complement functions are generated which include opsonization and phagocytosis of particles or microorganisms and cell lysis. (frontiersin.org)
  • Complement receptor 1 (CR1) is important in increasing phagocytosis. (labpedia.net)
  • Due to its destructive potential the complement system is heavily regulated but when activated it works largely by forming pore complexes as well as triggering acute inflammation and by promoting phagocytosis by macrophages and neutrophils. (vetbook.org)
  • Ehrlich believed that each antigen-specific amboceptor has its own specific complement, whereas Bordet believed that there is only one type of complement. (wikipedia.org)
  • Activation of complements leads to inflammation and localize the antigen or cause lysis. (labpedia.net)
  • The hublike organization of complement and its cell surface-directed action ( Fig. 1 ), involving some 50 constituents such as pattern-recognition molecules (PRM), protein components, proteases, regulators, and cell surface receptors, is essential for adjusting the complement response to different triggers ( Fig. 2A ). (jimmunol.org)
  • Baumann U and Schmidt RE (2001) The role of Fc receptors and complement in autoimmunity. (els.net)
  • Ravetch JV and Clynes RA (1998) Divergent roles for Fc receptors and complement in vivo. (els.net)
  • Over 30 proteins and protein fragments make up the complement system, including serum proteins , and cell membrane receptors . (wikipedia.org)
  • The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by three pathways: classical (CP), lectin (LP), and alternative (AP). (frontiersin.org)
  • Phagocytes have large numbers of iC3b receptors (complement receptors) which give opsonisation when engaged. (vetbook.org)
  • The third are cell surface receptors that bind to the products of complement activation and signal host cells to participate in inflammatory and immune reactions. (asmscience.org)
  • C2 (Complement C2) is a Protein Coding gene. (genecards.org)
  • Complement C2 is a protein that in humans is encoded by the C2 gene. (wikipedia.org)
  • The protein encoded by this gene is part of the classical pathway of the complement system, acting as a multi-domain serine protease. (wikipedia.org)
  • The C2 gene provides instructions for making the complement component 2 protein. (medlineplus.gov)
  • This protein helps regulate a part of the body's immune response known as the complement system. (medlineplus.gov)
  • When a foreign invader is detected, the complement pathway is turned on (activated) and the complement component 2 protein attaches (binds) to a similar protein called complement component 4. (medlineplus.gov)
  • This mutation prevents the production of any complement component 2 protein. (medlineplus.gov)
  • Recombinant protein encompassing a sequence within the center region of human Complement C2. (genetex.com)
  • Full length native complement component C2 protein isolated from human plasma. (abcam.com)
  • A complement protein attacking an invader. (wikidoc.org)
  • Kirjavainen V, Jarva H, Biedzka Sarek M, Blom A, Skurnik M, Meri S. Yersinia enterocolitica serum resistance proteins YadA and ail bind the complement regulator C4b-binding protein. (labome.org)
  • Meri T, Blom A, Hartmann A, Lenk D, Meri S, Zipfel P. The hyphal and yeast forms of Candida albicans bind the complement regulator C4b-binding protein. (labome.org)
  • The important protein components of complement are number C1 to C9 (they are numbered in their order of discovery however and not their order of action as you will see later). (vetsci.co.uk)
  • The protein encoded by this gene is part of the classical pathway of complement system.In the "classical" pathway of complement activation, activated C1 cleaves C4a and C4b, and cleaves C2 into C2a and C2b. (natvim.com)
  • The complement control protein (CCP) modules (also known as short consensus repeats SCRs or SUSHI repeats) contain approximately 60 amino acid residues and have been identified in several proteins of the complement system. (embl-heidelberg.de)
  • The sushi domain is also known as the complement controle protein (CCP) module or the short consensus repeat (SCR). (embl-heidelberg.de)
  • Three-dimensional structure of a complement control protein module in solution. (embl-heidelberg.de)
  • The complement control protein (CCP) modules (also known as short consensus repeats) are defined by a consensus sequence within a stretch of about 60 amino acid residues. (embl-heidelberg.de)
  • Both provide a path to the cleavage of C3 which is a central event in complement activation. (vetsci.co.uk)
  • The complement system consists of a series of cleavage reactions, whereby complement proteins are split off into fragments, and in certain steps bond to other complement fractions. (metabolichealing.com)
  • Cite this article as: Fagbohun, S.O., "IMMUNOLOGY: UNDERSTANDING THE COMPLEMENT SYSTEM," in ATG Ventures , 09/03/2019, https://atgventure.com/immunology-understanding-the-complement-system/ . (atgventure.com)
  • Three pathways of complement activation are now known: the alternative pathway, the classical pathway, and the lectin pathway. (asmscience.org)
  • The complement system is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promotes inflammation, and attacks the pathogen's cell membrane . (wikipedia.org)
  • The complement system can be recruited and brought into action by antibodies generated by the adaptive immune system . (wikipedia.org)
  • In the early 20th century, this controversy was resolved when it became understood that complement can act in combination with specific antibodies, or on its own in a non-specific way. (wikipedia.org)
  • The classical complement pathway typically requires antibodies for activation (specific immune response), while the alternative and mannose-binding lectin pathways can be activated by C3 hydrolysis or antigens without the presence of antibodies (non-specific immune response). (wikidoc.org)
  • These are called complement because it complements the antibacterial activity of some of the antibodies. (labpedia.net)
  • The following example shows the role of Antibodies and complement in the process of Bacteriolysis and Agglutination. (labpedia.net)
  • The complement system found in the blood of mammals is composed of heat labile substances (proteins) that combine with antibodies or cell surfaces. (atwebpages.com)
  • Monitoring patients with the C1q assay, which detects antibodies that fix complement, offers a minimally invasive means of identifying patients at risk for transplant glomerulopathy and graft loss. (labome.org)
  • 05). The results of our study suggest that anti-beta2GPI antibodies may play a role in GMT formation, and this process might involve complement activation. (labome.org)
  • Antibodies depend on complement for many of their biological activities. (vetsci.co.uk)
  • Type III hypersensitivity reactions occur when IgG and IgM antibodies bind to soluble proteins rather than cell surface molecules as in type II hypersensitivity reactions forming immune complexes that can deposit in tissues, leading to complement activation, inflammation, neutrophil influx and mast cell degranulation. (musicmarkup.info)
  • GENTAUR suppliers human normal cells, cell lines, RNA extracts and lots of antibodies and ELISA kits to Human proteins as well as Complement C4c, anti_human. (antibody-antibodies.com)
  • The complement system is a group of proteins that work together to destroy foreign invaders (such as bacteria and viruses), trigger inflammation, and remove debris from cells and tissues. (medlineplus.gov)
  • C3b has most important opsonizing activity Inflammation - by attracting macrophages and neutrophils Membrane attack - by rupturing cell wall of bacteria Overview[ edit ] Most of the proteins and glycoproteins that constitute the complement system are synthesized by hepatocytes. (rhein-main-verzeichnis.info)
  • 3) C4b and C2b combine and activate C3 which aids in inflammation, opsinization, and cystolysis. (cram.com)
  • Other complement proteins are attrachted to the surface of microbial cells, and when this happens C3 is activated into C3a, which helps in inflammation and C3b which helps in oppsinization and cystolysis. (cram.com)
  • Yet it has become evident that complement not only acts as a sensor of pathogens but also recognizes diseased and damaged host cells, and it closely collaborates with other immune and defense systems to eliminate potential danger ( 1 , 2 ). (jimmunol.org)
  • The past decade revealed a new perception of complement that reaches beyond the elimination of pathogens and includes key functions in immune surveillance, homeostasis, and mediation of inflammatory responses ( 1 , 2 ). (jimmunol.org)
  • Kupffer cells and other macrophage cell types help clear complement-coated pathogens. (wikidoc.org)
  • The complement system is a part of the immune system, consists of a series of proteins that interact with one another in a highly regulated manner, in order to eliminate pathogens. (microbeonline.com)
  • Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two fragments: C2b and C2a. (uniprot.org)
  • Component C2 is a serum glycoprotein that functions as part of the classical pathway of the complement system. (genecards.org)
  • In recent years, the complement system has been associated with a growing number of immunological and inflammatory conditions that include degenerative diseases, cancer, and transplant rejection. (jimmunol.org)
  • Given the classic perception of complement as defense system against microbial intruders, it may appear surprising that this ancient pillar of innate immunity was identified as a contributor in various inflammatory pathologies. (jimmunol.org)
  • It participates in the complement system ending with cell death. (wikipedia.org)
  • Two of the convertases are physiological complement enzymes, associate to the cell-surface and mediate the classical pathway (C4b2b3b, or C4b2a3b depending on source) or the alternative pathway (C3bBbC3b) of complement system. (wikipedia.org)
  • Researchers speculate that the dysfunctional complement system is unable to distinguish what it should attack, and it sometimes attacks normal tissues, leading to autoimmunity. (medlineplus.gov)
  • Alternatively, the dysfunctional complement system may perform partial attacks on invading molecules, which leaves behind foreign fragments that are difficult to distinguish from the body's tissues, so the complement system sometimes attacks the body's own cells. (medlineplus.gov)
  • The complement system is a key component of the innate immune system that is involved in eliminating unwanted self and nonself material via cellular and humoral mechanisms. (els.net)
  • Activation of the complement system via three pathways. (els.net)
  • Crawford K and Alper CA (2000) Genetics of the complement system. (els.net)
  • 1998) The Complement System. (els.net)
  • 1998) The Human Complement System in Health and Disease New York, NY: Marcel Dekker, Inc. (els.net)
  • The complement system consists of a number of small proteins found in the blood, in general synthesized by the liver , and normally circulating as inactive precursors ( pro-proteins ). (wikipedia.org)
  • Three biochemical pathways activate the complement system: the classical complement pathway , the alternative complement pathway , and the lectin pathway . (wikipedia.org)
  • Ehrlich introduced the term "complement" as part of his larger theory of the immune system. (wikipedia.org)
  • Ehrlich, therefore, named this heat-labile component "complement," because it is something in the blood that "complements" the cells of the immune system. (wikipedia.org)
  • Most of the proteins and glycoproteins that constitute the complement system are synthesized by hepatocytes . (wikipedia.org)
  • The complement system consists of a number of small proteins found in the blood, normally circulating as inactive zymogens . (wikidoc.org)
  • The term "complement" was introduced by Paul Ehrlich in the late 1890s, as part of his larger theory of the immune system. (wikidoc.org)
  • Complement System is a complicated system that is involved in the Immune System of an organism. (iahealth.net)
  • Some aspects of the immune system are adaptable however, the complement system is not one of these areas that are changeable. (iahealth.net)
  • Within the blood are several small proteins that play an important role in the complement system. (iahealth.net)
  • 2. Müller-Eberhard, H.J. Molecular organization and function of the complement system. (qmul.ac.uk)
  • Complement system is a group of more than 23 proteins that interacts with each other to opsonize the pathogen and induces a series of inflammatory responses that helps to generate immune response against that pathogen. (periobasics.com)
  • The principal participants in this system are 11 proteins designated C1 through C9, B, and D . Term complement means to augment the effect of other complements of immune system. (periobasics.com)
  • In the following sections we will try to understand the functioning of complement system, its regulation and disorders related to its function and regulation. (periobasics.com)
  • Complement system can be activated by immune complexes and immunologic molecules like endotoxins. (periobasics.com)
  • The components of the complement system can be found throughout the body in fluids, providing the body with a systemic means of protection. (vetsci.co.uk)
  • The effects of these polysaccharides have far-reaching possibilities for various aspects of the human immune system, including those relating to innate, complement immunity. (metabolichealing.com)
  • The complement immune system is a key part of the ancient, innate immune response. (metabolichealing.com)
  • Both mold exposure and Lyme disease are associated with higher C4a levels ( R ). CFS/ME is associated with higher C4a levels ( R ). The significance of an elevation of C4a in these conditions is associated with activation of the lectin pathway of the complement immune system, the involvement of MASP-1, MASP-2, and MBL. (metabolichealing.com)
  • Research has found Lion's Mane is capable of inhibiting reverse transcriptase of HIV retrovirus ( R ), as well as increasing the expression of the antioxidant genes Nrf2 and gamma glutamyl cysteine (which activates glutathione directly) ( R ). Lion's mane also has neuroprotective and neurotrophic effects, by acting to increase NGF (nerve growth factor) ( R ). Does lion's mane activate the complement immune system? (metabolichealing.com)
  • What role if any do other polysaccharides play in the complement immune system? (metabolichealing.com)
  • The early step of complement system varies in different pathways. (microbeonline.com)
  • Physiological barriers such as temperature, pH and the complement system. (wordpress.com)
  • The complement system recognizes features of microbial surfaces and marks them for destruction by coating them with C3b. (wordpress.com)
  • The complement system is designed to mobilize a large number of immune effector mechanisms when it detects infected or injured self tissues. (asmscience.org)
  • Thus, complement constitutes the fundamental proinflammatory response system that can trigger and regulate the remainder of the immune response. (asmscience.org)
  • There is also a darker side to the complement system. (aurignacien.com)
  • The Complement System Andrew E Thompson MD FRCPC Fellow in Rheumatology University of British Columbia. (slideplayer.com)
  • The innate immune system comprises physical, chemical, and biological barriers (e.g., the skin , gastric acid , commensal organisms ) and both cellular (e.g., granulocytes , natural killer cells , mast cells ) and humoral ( complement system ) defense mechanisms . (amboss.com)
  • Within the complement system C1-INH blocks the activation of C1 and the rest of the classic complement pathway by binding to C1r and C1s. (affinitybiologicals.com)
  • These modules have been identified more than 140 times in over 20 proteins, including 12 proteins of the complement system. (embl-heidelberg.de)
  • Complement component C2, inhibiting a latent serine protease in the classical pathway of complement activation. (medlineplus.gov)
  • This infers resistance to complement-mediated cell lysis, allowing parasite survival and infection. (genecards.org)
  • Type I human complement C2 deficiency. (wikipedia.org)
  • At least five mutations in the C2 gene have been found to cause complement component 2 deficiency. (medlineplus.gov)
  • More than 90 percent of people with complement component 2 deficiency have a mutation that deletes 28 DNA building blocks (nucleotides) from the C2 gene. (medlineplus.gov)
  • It is unclear how complement component 2 deficiency leads to increased susceptibility to autoimmune disorders. (medlineplus.gov)
  • It is likely that other factors, both genetic and environmental, play a role in the variability of the signs and symptoms of complement component 2 deficiency. (medlineplus.gov)
  • Linton S (2001) Animal models of inherited complement deficiency. (els.net)
  • O'Neil KM (2000) Complement deficiency. (els.net)
  • Defects in C2 are the cause of complement component 2 deficiency (C2D) [MIM:217000]. (abcam.com)
  • A deficiency of the complement classical pathway associated with the development of autoimmune disorders, mainly systemic lupus erythematosus. (abcam.com)
  • Patients with complement component 2 deficiency are also reported to have recurrent or invasive infections. (abcam.com)
  • It becomes evident that excessive activation or insufficient control of complement activation on host cells can cause an immune imbalance that may fuel a vicious cycle between complement, inflammatory cells, and tissue damage that exacerbates clinical complications. (jimmunol.org)
  • Although the exact involvement of complement needs to be carefully investigated for each disease, therapeutic modulation of complement activity emerges as an attractive target for upstream inhibition of inflammatory processes. (jimmunol.org)
  • This review provides an update about the functional and collaborative capabilities of complement, highlights major disease areas with known complement contribution, and indicates the potential for complement as a focal point in immunomodulatory strategies for treating inflammatory diseases. (jimmunol.org)
  • In the worst case, a vicious cycle between tissue damage, complement activation, and immune attack perpetually re-creates inflammatory stimulators rather than resolving them. (jimmunol.org)
  • In view of this upstream position in inflammatory homeostasis, there is growing interest in understanding the role of complement in pathological processes and in exploiting complement targets for therapeutic modulation ( 3 , 4 ). (jimmunol.org)
  • Fortunately, our knowledge about the functions of complement in health and disease has much improved, and new discoveries have revealed a fascinating cross-talk network that ties complement closely into the immune-inflammatory network ( 1 , 5 ). (jimmunol.org)
  • Once complement is activated, its components participate in virtually every aspect of the inflammatory response. (labpedia.net)
  • Complements are activated only during inflammatory reactions. (microbeonline.com)
  • Nevertheless, the parasite uses a sequence of events in order to escape from complement-mediated lysis. (frontiersin.org)
  • In prezenta ionilor de Mg 2+ , C4b leaga C2 care este clivat, la randul sau, in doua fragmente: cel mare, C2a, ramane legat pe C4b si constituie complexul C4b2a, denumit convertaza C3, iar cel mic, C2b, este eliberat in plasma. (lamedic.ro)
  • C2a binds C4b forming the C4b2a complex whereas C2b goes away. (microbeonline.com)
  • The lectin pathway of complement activation is when mannose-binding lectin (MBL) and ficolins recognize and bind to carbohydrates on the pathogen surface. (wordpress.com)
  • Deficiencies of an early component of the classical complement pathway (C1q, C1r, C1s, C2, C4) have been associated with lupus like autoimmune conditions. (mastattack.org)
  • When expanding the autoimmune profile to include "lupus-like" conditions such as those often associated with complement deficiencies, a much higher prevalence of autoantibodies was found in HAE patients. (mastattack.org)
  • The inner portion of 1gm plus c2b of complement deficiencies or a way that the partition coelticient in- the receptor. (safeembrace.org)
  • The catalytic subunits of these multimolecular proteases are C2b and Bb. (wikipedia.org)
  • Synthesis of proteases specifically against complement proteins degrades complement components. (aurignacien.com)
  • Many complement proteins are proteases that are synthesized as inactive pro-enzymes (zymogens) - C1(C1q:C1r2:C1s2) - Collectins or Ficolins (MASP1, MASP2) What is the function of Complement? (slidegur.com)
  • In this review, we aim to present an overview on the strategies used by T. cruzi in order to circumvent the activation of complement and, consequently, its biological effects. (frontiersin.org)
  • One molecule of IgM can activate complement but activation of IgG is with the help of cross linking 2 molecules. (periobasics.com)
  • This difference accounts for the observation that a single molecule of IgM bound to a red blood cell can activate the classical complement pathway and lyse the red blood cell while some 1000 molecules of IgG are required to assure that two IgG molecules are close enough to each other on the cell surface to initiate C1q binding. (78stepshealth.us)
  • 1. A method for diagnosing, or identifying a predisposition to the development of, a macular degeneration-related disorder in a subject, comprising detecting in a biological sample from the subject an abnormal activity or an abnormal level of at least one complement pathway associated molecule, or an abnormal cellular activity mediated by the complement pathway. (patentsencyclopedia.com)
  • 20. A method for treating or preventing the development of a macular degeneration in a subject, comprising providing to the subject an effective amount of a therapeutic agent which modulates an activity or expression level of at least one complement pathway associated molecule, or a cellular activity mediated by the compelement pathway, wherein the subject is suffering from or at risk of developing a macular degeneration-related disorder. (patentsencyclopedia.com)
  • 1. Kerr, M.A. The second component of human complement. (qmul.ac.uk)
  • Complement component C3 is cleaved by: A. C3b The classical and alternative pathways meet at complement component: A. C3. (rhein-main-verzeichnis.info)
  • Only IgM and IgG can activate complement. (periobasics.com)
  • Only IgM and certain IgG subclasses can activate complement this way. (vetbook.org)
  • While research has not yet demonstrated its specific complement effects, a mushroom hericium erinaceus, aka Lion's mane possesses one of the highest polysaccharide concentrations. (metabolichealing.com)
  • Volanakis JE (1995) Transcriptional regulation of complement genes. (els.net)
  • Xaa bond in complement component C5 alpha-chain to form C5a and C5b. (uniprot.org)
  • A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. (bireme.br)
  • A third pathway of complement activation, the lectin pathway, has recently been defined but, like the alternative pathway of complement activation, likely arose during evolution prior to the classical pathway. (asmscience.org)
  • the resultant C4bC2 complex is then cleaved by C1s or MASP2 into C2a and C2b. (wikipedia.org)
  • The bound C3b activates the next complement component C5, which again splits up into the subcomponents C5a and C5b upon activation. (vetsci.co.uk)
  • Complement proteins are enzymatic in nature and circulate in the body in inactive form. (atgventure.com)
  • Complement has been argued to have a component or factor in certain disease. (iahealth.net)
  • factor B a complement component that participates in the alternative complement pathway. (thefreedictionary.com)
  • AK304045 - Homo sapiens cDNA FLJ55673 complete cds, highly similar to Complement factor B precursor (EC 3.4.21.47). (usc.edu)
  • functionally the larger peptide of Complement Factor 2( C2) had coiled C2a. (ersichtlich.de)
  • The solution structure of the 16th CCP module from human complement factor H has been determined by a combination of 2-dimensional nuclear magnetic resonance spectroscopy and restrained simulated annealing. (embl-heidelberg.de)
  • AK300892 - Homo sapiens cDNA FLJ54076 complete cds, highly similar to Complement C2 precursor (EC 3.4.21.43). (usc.edu)
  • AK222537 - Homo sapiens mRNA for complement component 2 precursor variant, clone: adSE01995. (usc.edu)
  • Among its related pathways are Immune response Lectin induced complement pathway and Complement Pathway . (genecards.org)
  • C5 is cleaved into C5a/b that initiates the assembly of the terminal complement components. (wordpress.com)
  • Deciphering complement mechanisms: the contributions of structural biology. (uab.edu)
  • Low complement C4B gene copy number predicts short-term mortality after acute myocardial infarction. (labome.org)
  • Primary structure of human complement component C2. (wikipedia.org)
  • Abcam's Complement C2 Human in vitro ELISA (Enzyme-Linked Immunosorbent Assay) kit is designed for the quantitative measurement of Complement C2 in CSF, plasma, serum, saliva, and cell culture supernatants. (abcam.com)
  • These proteins can be found on every human cell and prevent for complement to occur to these cells. (iahealth.net)
  • X04481 - Human mRNA for complement component C2. (usc.edu)
  • Binding of C4bp could help Y. enterocolitica to evade complement-mediated clearance in the human host. (labome.org)
  • IgM and certain subclasses of IgG (human IgG1, IgG2, and IgG3) can activate the classical complement pathway. (78stepshealth.us)
  • More than 20 types of complements are present in serum, found circulating normally in human body in inactive forms (called as zymogens or proenzymes) . (microbeonline.com)
  • Complement C4c, anti_human Human samples 80 % of the research is conducted on human samples. (antibody-antibodies.com)